Managing multiple WordPress sites can feel like playing an endless game of dashboard hop – logging in and out, repeating the same updates, and wasting time on work that could be done once.

If your sites are related (part of the same business, organisation, or project), there’s a better way. A WordPress Multisite network lets you run them all from a single installation, with one login, shared themes and plugins, and updates that apply across the board.

In this guide, you’ll learn exactly how to merge your existing WordPress sites into a single multisite network. We’ll cover when multisite is the right choice (and when it isn’t), how to prepare your sites for migration, and the step-by-step process for bringing all your content, themes, and media together under one roof.

We will also provide a detailed pre-migration checklist to prepare your sites for a smooth transition and step-by-step instructions to activate your network and migrate all your content, themes, plugins, and media files.

Let’s get started!

The Benefits of a Multisite Network

Moving your individual sites into a multisite network might seem like a bit of work upfront, but the long-term benefits are definitely worth it. Here’s why it’s such a great idea:

  • Centralized Management: This is the biggest win! Instead of juggling multiple usernames and passwords, you can manage every single one of your websites from a single dashboard. With a special “Super Admin” role, you have the power to oversee everything from one convenient location.
  • Efficient Updates: We all know how important it is to keep WordPress, themes, and plugins updated. With a multisite network, you only have to perform an update once. When you update a theme or plugin, that update becomes available across all the sites in your network instantly. This saves time and ensures all your sites are secure and running the latest versions.
  • Resource Savings: Every WordPress installation takes up space on your hosting server. When you have multiple separate sites, you have multiple copies of WordPress core files. A multisite network uses just one set of these core files for all your sites, which means it uses less server space and can be more efficient to run.
  • Consistency: If you want all your sites to have a similar look and feel, then you can use Multisite Network to share themes and plugins across the network. This makes it incredibly simple to maintain a consistent brand and user experience on all of your websites.

When Should You Not Merge Your Sites? 

While a multisite network is a fantastic tool, it’s not the perfect solution for every situation. Before you go all-in, it’s important to understand when keeping your websites separate is better.

The most important thing to remember is that all the sites in a multisite network are fundamentally connected. They share the same core WordPress files and the same user database.

This is why a multisite network is the perfect choice when all your websites are related to each other. For example, it’s great for a single company that needs separate sites for its different departments, office locations, or regional branches. All of these sites operate under the umbrella of one parent company.

However, you should not use a multisite network when managing websites for two completely different companies or brands unrelated to each other. For instance, you wouldn’t want to run the website for your freelance photography business and the website for your brother’s local pizza shop on the same multisite network. Because they share a user database, it could create confusion and potential security issues. You want to keep completely separate businesses, well, separate!

If your main goal is simply to manage multiple, unrelated sites from one convenient dashboard without having to log in and out all the time, then a multisite network isn’t the right tool for the job. You should look at our post on the “10 Best WordPress Management Tools To Easily Manage Multiple Websites” to find the perfect solution for your needs.

While creating a multisite network is awesome, merging existing sites into it can be a bit tricky. It’s a process that requires care and attention to detail. You might run into some bumps along the way, like issues with URLs not redirecting correctly, differences in how the databases are structured, or site-specific settings that don’t initially play nicely with the network.

It’s very common to do some manual tweaking after the main work is done, such as double-checking your website links (permalinks) or adjusting a few settings to ensure everything is compatible with the multisite setup. Don’t let this scare you, but being prepared is good!

Additionally, your site may have some downtime, so prepare accordingly.

Part 1: Pre-Migration Checklist 

Before you dive in, taking a few preparatory steps will save you from future headaches and make the whole process much smoother. 

  • Delete Old Data: Before you pack everything up, look around your current site and see if you can tidy up anything. This is a great time to get rid of any spam comments, delete old post drafts that you’ll never use, and remove any images or media files that are no longer needed. Every piece of data on your site must be packed up, moved, and then unpacked on the new site. The less you have to move, the faster the entire merging process. Plus, it will make your backup file much smaller and easier to manage.
  • Create a Complete Backup: This is, without a doubt, the most important step. Before you change any settings, you need a complete backup of your entire website. This includes your database, all your media files, themes, and plugins. If anything goes wrong, you can restore your site to exactly how it was before you started. If you are using RunCloud, you can do this with a simple click from the RunCloud dashboard.
  • Verify Hosting Support: Not all web hosting plans are created equal. Some, especially budget-friendly shared hosting plans, may not support or allow a WordPress Multisite network. Before you begin, contact your hosting provider’s support team or check their documentation to confirm that your plan can handle a multisite installation. If you are using RunCloud, you can continue safely, as RunCloud doesn’t impose any restrictions on WordPress Multisite installations.
  • Check for Plugin and Theme Compatibility: While many plugins and themes work perfectly in a multisite network, some don’t. Take a moment to review your most essential plugins and themes to make sure they are “multisite compatible.” A quick search on the plugin or theme’s page in the WordPress repository or the developer’s website will usually give you the answer.
  • Enable Pretty Permalinks: If your website’s links look something like yourdomain.com/?p=123, it’s best to change them to a more user-friendly and SEO-friendly structure, like yourdomain.com/sample-post. These are called “pretty permalinks.” Having this structure enabled before you start can prevent link-related issues after the merge. You can find this setting in your WordPress dashboard under “Settings” -> “Permalinks.”
  • Enable Maintenance mode: It is recommended that you enable WordPress maintenance mode on your old site by executing the wp maintenance-mode activate command. This will block users from accessing your site and reduce the chances of your data getting corrupted on highly dynamic sites.
  • Deactivate All Plugins: On the individual website that you are planning to merge, it’s a smart move to deactivate all of your plugins right before you export your content. Sometimes, plugins can interfere with the export process and cause conflicts.

Part 2: Activating Your Multisite Network

This next part is for anyone who has not yet built a multisite network. However, if you already have a multisite network up and running, you’re ahead of the game! Feel free to jump to the next section.

There are two main ways to create a Multisite network:

Method 1: Creating a brand-new multisite network

This is the perfect option if you’re starting from scratch, maybe because you’re moving to a new hosting provider or haven’t even built the main site for your network yet. The biggest advantage here is that you begin with a completely clean WordPress installation, which is a great way to ensure you don’t run into any potential conflicts from old plugins or settings. 

If you are using RunCloud, you can install a multisite network with only a few clicks from your RunCloud dashboard. 

Method 2: Converting an existing WordPress site into a multisite network

If you already have your primary website up and running, you should follow this method. For example, if your main business website is already built and you want to add a blog or a store as separate sites within the same network, you would convert your existing site to become the “command center” of your new network.

  1. Edit Your wp-config.php File: The first step is to edit the wp-config.php file in your main WordPress folder and add the following line of code: define(‘WP_ALLOW_MULTISITE’, true);
  2. Begin the Network Setup: Once you’ve saved the change to your wp-config.php file, log in to your WordPress dashboard. A new option will have magically appeared! Navigate to Tools and then click on Network Setup to get started.
  3. Choose Your URL Structure: This is a very important step, so take a moment to think it through. WordPress will ask you to decide how the web addresses for your new sites will be formatted. You have two choices: Subdomains (which look like site1.yourdomain.com) or Subdirectories (which look like yourdomain.com/site1). This choice is permanent and difficult to change later, so pay close attention and choose the one that makes the most sense for your project’s future.
  1. Install the Network: After you’ve made your choice, simply follow the on-screen instructions provided by WordPress. It will generate two snippets of code for you to copy and paste. One snippet will go back into your wp-config.php file (the same one from Step 1), and the other will go into a file called .htaccess (a server configuration file in the same directory). Once you’ve carefully added the code and saved the files, your multisite network will be active and ready to go

Part 3: Merging WordPress Sites 

After performing all the above steps, we are finally ready to start the merging process. You must perform the following steps for each site you want to merge into your multisite network.

Step 1: Export Your Content

  • From the individual WordPress site you want to merge, go to “Tools” -> “Export“.
  • Select “All content” and download the XML (WXR) file. This file contains your posts, pages, comments, and other content.

Step 2: Create a New Site in Your Network

Next, you need to create a new site in your Multisite network. This is where you will import the data we exported in the previous step. 

  • In your multisite dashboard, navigate to “My Sites” -> “Network Admin” -> “Sites”.
  • Click “Add New” and create a new, empty site for the content you are about to import.

Step 3: Import Your Content

  • Go to the dashboard of the newly created site.
  • Navigate to “Tools” -> “Import” and run the WordPress Importer.

On the next screen, you must upload the XML file you exported in Step 1. Depending on the size of your site, you may run into issues with max_upload_size or PHP memory limits. You might need to contact your host to temporarily increase these.

  • You will be prompted to assign the imported content to existing users or create new ones. Be sure to check the box to download and import file attachments. When you check this box, the WordPress Importer does two things:
    • It downloads the files: It reads through all your posts and pages, finds where you’ve inserted images or other media (like PDFs or audio clips), and physically downloads a copy of each file from your old, separate site to your new site’s Media Library.
    • It updates the links: After downloading the files, it automatically updates the links within your posts and pages to point to the new location of those files inside your multisite network. This ensures that all the images and media show up perfectly when you view a blog post on your new site.

What Happens if You Don’t Check the Box?

If you forget to check this box, only the text content of your posts and pages will be imported correctly. Your website will look like it’s full of broken images. Because the posts will still contain image links pointing back to the Media Library on your old, separate website. When you take that old site offline, all those image links will break permanently, and the images will disappear from your new site.

Step 4: Migrate Your Themes, Plugins, and Media

Now that you’ve successfully imported your posts and pages, you’ve brought over the “soul” of your website. The next step is to bring over its “look and feel”, i.e., your themes, plugins, etc.

If you decided not to download and import attachments in the previous step, then you can also import them manually in this step. This is where things get a bit more technical.

While you can upload themes and plugins through the WordPress dashboard, moving a large library of media files efficiently and correctly often requires diving into the command line. Being comfortable with basic Linux commands is a huge advantage for a smooth migration, especially when moving from one server to another.

Migrating Your Themes and Plugins

First, you must install all the necessary theme and plugin files on your multisite network. You can easily download new themes and plugins by navigating to “Network Admin” -> “Plugins.” Once they are installed, click on “Network Activate” to make them available for all the sites in your network.

Installing plugins in a WordPress multisite network

Migrating Your Media Files via The Command-Line 

Your media files (everything in your old site’s wp-content/uploads folder) must be moved to a special directory in your multisite network.

Each network site has its unique uploads folder, located at wp-content/uploads/sites/X, where X is the unique Site ID. You can easily find the Site ID by going to your “Network Admin” > “Sites” dashboard and hovering over or clicking “Edit” on your new site; the URL will contain its ID.

For example, in the above screenshot, the site ID is 4.

Manually downloading and re-uploading hundreds or thousands of files is slow and prone to errors. The ideal method is to copy the files directly from your old server to the new one using the command line.

  1. Connect to Your New Server: You’ll first need to connect to your new server’s command line using SSH (Secure Shell). Your hosting provider can give you the credentials and instructions for this.
  2. Navigate to a temporary directory: Once connected, navigate to a temporary folder where you want to temporarily upload your media files. The command will look something like this:
mkdir /tmp/myWordPressContent
cd /tmp/myWordPressContent
  1. Pull Files from the Old Server Using rsync: Rsync is a powerful command-line tool that efficiently synchronizes or copies files between two locations. It’s fast, reliable, and perfect for this job. From inside your new site’s uploads folder, you would run a command like this:
rsync -avz --progress [email protected]:/path/to/old/site/wp-content/uploads/* .

Let’s quickly break down that command:

  • rsync -avz --progress: This tells rsync to run in archive mode (preserves file permissions and timestamps), be verbose (show what’s happening), compress the data to speed things up, and show a progress bar.
  • [email protected]:/path/to/old/site/wp-content/uploads/*: This is the source. It’s the full path to all the files (*) inside the uploads folder on your old server.
  • .: This is the destination. The single dot means “copy everything to my current directory.”

Note: If both your old and new sites are on the same server, you don’t need to copy the files to a different folder. You can use the cd command to navigate to the /wp-content/uploads/ folder of the old site and proceed to the next step.

Importing the Media to WordPress

Simply copying the files onto the server isn’t enough. You’ve moved the files, but your WordPress database has no idea they exist, and they won’t appear in your Media Library. You need to tell WordPress to scan the folder and register each file.

With WP-CLI, you can run the wp media import command. This command goes through a directory of files and properly imports each into the WordPress Media Library, creating all the necessary thumbnails along the way.

You would run a command like this:

wp media import --url=newsite.yourdomain.com --path=/path/to/your/multisite/ ./*

Let’s break that down:

  • wp media import: This tells WordPress we are performing a media import operation.
  • --url=newsite.yourdomain.com: This is essential for multisite. This flag tells WP-CLI exactly which site in the network these media files belong to.
  • --path=...: This provides the full path to your multisite’s root WordPress installation, so WP-CLI knows where to find the core files.
  • ./*: This is the path of media files you want to import. The ./ means the current directory, and * means all the files in this directory.

When you fill in all the necessary values, the final command should look like this:

wp media import --path=/home/runcloud/webapps/app-franecki --url=https://app-franecki.corxbbfou5-yk26eoz8z479.p.temp-site.link/site2/ ./*

Completing this final command-line step ensures that all your migrated images and files are correctly registered and will appear perfectly within your new site’s Media Library.

Part 4: Post-Migration Checks

The heavy lifting is done, and your site has been moved into its new home, but don’t pop the champagne just yet! To ensure a seamless transition for both you and your visitors, it’s important to run through a final checklist. These small steps will catch any potential issues and ensure your new site runs perfectly.

  • Check and Reset Your Permalinks: Sometimes, the URL structure can get a little confused after a migration. A broken link is bad for your visitors and your SEO. Fortunately, the fix is very simple: go to the dashboard of your new site, navigate to Settings > Permalinks, and without changing anything at all, just click the “Save Changes” button. This simple action forces WordPress to rebuild its link structure and fixes most common link-related issues.
  • Verify All User Roles and Permissions: You must pay close attention to this area. The standard WordPress Importer is great for content, but does not import user roles. You will need to re-assign roles manually. Go to the Users tab on your new site’s dashboard and double-check that every user has the correct role (e.g., Administrator, Editor, Author). 
  • Review Your Settings from Top to Bottom: If you performed any tweaks to your original site, they didn’t come over with the import file. You’ll need to go through your settings and configure them again. Pay special attention to:
    • Theme Options: Go into your theme’s settings panel and set up your logos, colors, fonts, and layout options.
    • Plugin Settings: Check the settings for your key plugins, like contact forms, SEO tools, and caching plugins.
    • Widgets: Your widgets will likely need to be re-added and configured. Go to Appearance > Widgets to drag and drop them back into your sidebars and footers.
  • Test Everything… and We Mean Everything!
    Put on your visitor’s hat and browse your new site thoroughly. Click through the navigation menu, read a few blog posts, and ensure all the images display correctly. Test every key functionality; submit a message through your contact form, test your search bar, and go through a test purchase process if you have a store.
  • Add Redirects from the Old Site to the New: To avoid losing your hard-earned search engine rankings and to prevent visitors from landing on a dead page, you must set up 301 redirects. A 301 redirect tells browsers and search engines that your site has moved permanently. You’ll need to redirect traffic from your old standalone site’s URL to its new address within the multisite network (e.g., from oldsite.com to yournetwork.com/newsite). This can be easily done by adding rules to your .htaccess file.

After Action Report

Merging your WordPress sites into a multisite network is a powerful way to streamline your workflow and efficiently manage all of your websites. While the process can have challenges and technical hurdles, careful planning and following these steps will help ensure a smooth and successful transition.

Tired of the Command Line? Let RunCloud Handle It.

You’re not alone if you feel overwhelmed after reading through the steps involving SSH, rsync, and WP-CLI. Managing a Linux server can be complex and time-consuming, taking you away from what you do best – running your business.

That’s where RunCloud comes in.

We believe server management should be simple. Our platform provides a clean, powerful control panel that makes it incredibly easy to deploy websites, manage databases, and secure your server without ever touching the command line. You can focus on growing your business and creating great content, and leave the server management to us.

Ready to experience a faster, simpler way to manage your WordPress sites? Sign up for a 7-day free RunCloud trial today!